Laminated material



Feb. 12, 1935. w. E. GWALTNEY 1,991,090

LAMINATED MATERIAL Filed June 16, 1930 E's mm? ELY-'11 I INVENTOR MY/IOIDE k a/ffl y.

A+TORNEY Patented Feb. 12, 1935 1,991,090

UNITED STATES PATENT OFFICE,

LAMINATED MATERIAL William E. Gwaltney, Trafford, Pa., assignor to Westinghouse Electric & Manufacturing Company, a corporation of Pennsylvania Applicationlunelfi, 1930, Serial No. 461,284

Claims. (01. 154-2) My invention relates to composite laminated the composite sheets of molded material produced material and more particularly to methods of by the foregoing methods, it was found that the producing composite plates of such material dull effect was caused by high and low spots in which have an exterior satin-like the finished article which refracted the light in 5 The principal object of my invention is .to such manner that a dull bloom or lifeless effect 5 provide a method of producing laminated matewas produced.

rial which comprises interposing a plurality of Ihave discovered, however, that, if the surfaces layers of fibrous material, the outer sheets of of the plates which come into contact with the which have prints thereon resembling wood belaminated articles during the molding operation tween plates which have been etched or treated are treated by a special process, they will impart 10 in a specified manner and molding the sheets the desired finish to the surface of the molded under heat and pressure, thereby producing a material, and, when the outer sheets have deflnal article having an exterior finish closely resigns printed thereon resembling wood, a product sembling the best grades of hand-rubbed hard will be produced which resembles the best grades woods. of hand-rubbed wood. 15

In manufacturing laminated sheet material, My invention will be better understood by refibroussheets are first impregnated with'a binder ferring to the accompanying drawing, in which which iscapable of being hardened underheat Figure 1 is a plan ,view of a plate etched by and pressure, such as a phenolic condensation my improved process;

product or one of the various urea or thiourea Fig. 2 is an elevational view of a press show- 20 resins-or mixtures thereof, and a plurality of such ing the treated plates in partial cross section and sheets are subjected :to heat and pressure between a plurality of laminated sheets interposed between polished ..metallic' plates to form a composite the plates; article. In certain embodiments, itisdesirable to Fig. 3 is an elevational view of an apparatus produce a finish resembling wood or some fabric. for moving the plate in contact with a rotating 25 It has, accordingly, beenthe practice to utilize brush; and outer sheets having designs printed thereon re- Fig. 4 is a cross sectional view of the apparatus, sembling the design of the kind of material to be taken on the line IVIV of Fig. 3. represented. Referring to Figs. 1 and 2 of the drawing, the

' Laminated articles Produced in uc manner, numeral 1 designates a plate which has been 30 however, are not entirely satisfactory because, treated by my process. My improved plates may when highly polished pressing plates are ein-' be utilized for molding fibrous sheet material ployed, a finished product is obtained that has a in a manner well known in the art. For exmore or less wavy appearance which is not pleasample, the treated surfaces of a pair of plates ingtothe eye and is readily distinguishable from are placed in engagement with a plurality of 35 wood having a hand-rubbed finish. sheets of fibrous material which have been im- Various attempts have been made to etch or pregnated with a suitable binder, such as a phescore the surfaces of the metallic plates which are nolic condensation product, as shown at 2 in Fig. placedincontact withthe laminated sheets during 2 of the drawing, Heat and pressure are then 40 the molding operation, so that a satin-like finish applied, in the usual manner, to harden the 40 -will be imparted to the finished article. For exbinder and form the composite article. 7 ample, they have been subjected to a sand-blast- My improved method of producing the satin- Operation in which different pressures of air finish on the plate is illustrated in Figs. 3 and 4 and various abrasives were utilized. Attempts of the drawing, in which the numeral 3 designates were also made to treat the plates with the usual a table or bench which serves as a support fof 45 sanding machines. The results, however, were a screw-threaded shaftl. Extending upwardly not satisfactory because, when pressing plates from the table 3, are brackets 5 which support treated in the manner specified were employed as a table 6 on which the plate 1 to be treated is the contacting sheets in producing laminated artiplaced. The table 6 is provided with a downcles, a dull, bloom effect was imparted to the finwardly-extending lug 7, having an aperture there- 50 ished product, and, although the wavy, polished in which is in screw-threaded engagement wlth appearance was removed, the design of the surface the shaft 4. A brush 8, provided with a pair of sheets appeared lifeless, and the finished article pintles 9, is journalled in bearings 10. One of did not have the desired satin-like finish. the pintles 9 is extended through the bearing r Upon making a microscopical examination of 10 and is provided with a gear wheel 11 that vided with a worm gear wheel 14 which meshes with a worm 15 formed upon the shaft of ,a motor 16.

During the operation of the device, the motor 16, in conjunction with the gear wheels 14 and 15, rotates the shaft 4 in bearings provided in supports 17. As the shaft rotates, the table 6, the lug 7 of which is in screw-threaded engagement with the shaft, is moved forward to bring the plate 1 into contact with the brush 8. The brush 8 is provided with wire bristles 18 and is rotated at a definite'speed by means of the motor 13, the gear 12, on the shaft of which, meshes with the gear 11 attached. to the pintle 9 of the brush. The platesare successively moved forward and backward, until the desired finish is produced. I have found that, where the plate is moved in contact with the brush from 10 to 50 times, the desired finish is obtained.

In order to produce the desired results, the bristles of the brush must be of a definite size. The speed at which the brush is rotated over th plate must also be maintained within certain definite limits. Satisfactory results will be produced when a brush' having a diameter ranging from .008 of an inch to .01 of an inch is utilized and the peripheral speed of the brush is maintained at 3000 to 3800 feet per minute.

A peripheral speed below 3000 feet per minute gives a crystalline effect to the surface which produces a bloom that is imparted to the finished laminated sheet during the molding operation, and, when the peripheral speed is maintained above 3800 feet per minute, a polished effect is obtained. A wire brush having bristles .009 of an inch in diameter produces a smooth, satin-finish, while a larger wire,'for example, one having a diameter of .012 of an inch, gives a coarser finish, and the treated surface has a crystalline appearance. In actual practice, I have found that, by employing a. brush provided with bristles each having a diameter of .009 of an inch, and revolving the brush at a peripheral speed of approximately 3300 revolutions per minute, a satin-finish isproduced which is free from scratches and high and low spots, even when highly magnified.

As will be readily understood, the friction of the wire brush upon the surface of the plate during the process generates a certain amount of heat which is necessary for the successful operation of the process. The temperature of the plate, however, should not be permitted to exceed 105 0.; otherwise, a glossy effect will be produced. I prefer to conduct the process in such manner that, as the plate moves uniformly in contact with the bristles of the brush, the rotation of the brush will be maintained at such speed that sufficient heat will be generated by friction to maintain the plate at a temperature of to C.

After the plate has been provided with a satin finish, an electrodeposited layer of chromium may be deposited upon its surface. The chromium not only increases the hardness of the press-- ing plate but also increases its resistance to corrosion. A chromium-plated pressing plate, however, is not absolutely essential, as good results have been obtained with other metals.

While .I have described my invention in considerable detail and have disclosed specific embodiments, it will be understood that I do not desire to limit myself to the foregoing examples, which should be construed as illustrative and not by way of limitation. For example, any desired method of uniformly moving the plate in contact with the brush may be provided, or, if desired, the plate may be maintained stationary and the rotating brush moved uniformly over its surface.

If the temperature of the plate during the operation of the process has the tendency to exceed 100 C., it may be cooled by passing cooling fluid through the supporting table 6, in which event, the rotative speed of the brush may be increased. In the particular examples given, I have specified that my improved pressing plates are particularly desirable for producing a satin finish on laminated material having outer surfaces resembling wood. I do not desire to limit my invention.in this respect, however, because, obviously, they may be utilized in moldinglaminated articles, such, as panels, in which the outer sheet is formed in solid colors or on which various designs are printed.

Other modifications of my invention will be; come apparent to those skilled in the art. I desire, therefore, that only such limitations shall be imposed thereon as are required by the prior art and the appended claims. I claim as my invention:

1. A laminated article comprising a plurality of layers of sheet material cemented together by a heat-hardened binder, the surfaces of the outer layers of said sheets having asatin-like finish.

2. A laminated product comprising. a pluralityof layers of sheet material bound together by a heat-hardened binder, the surface sheets having prints thereon resembling wood and being characterized by having a finish resembling hand-' rubbed wood.

3. The process of producing a laminated article which comprises impregnating a plurality of sheets of fibrous material with a binder capable of being hardened under heat and pressure, interposing the sheets between plates having a satin finish and molding the sheets together into a composite structure under heat and pressure. 4. The process of producing a laminated article having a surface resembling the grain of,

wood which comprises impregnating a plurality of sheets of fibrous material with a binder, in-' terposing said sheets between two sheets of fabric having prints thereon resemblingwood which are also impregnated with a binder, placing pressing plates having a satin-like finish in engagement with the assembled layers and molding the sheets together under heat and pressure to form a composite article.

5. The process of producing a laminated article having a surface resembling the grain of handrubbed wood which comprises assembling a plu-' rality of layers of fibrous material witha phenolic condensation product, interposing the layersbetween two sheets of fibrous material having prints thereon resembling wo0d, placing a metallic pressing plate having a satin-finished surface in engagement with the assembled layers and molding the fibrous material under heat and pressure, thereby imparting a finish to the composite article resembling hand-rubbed wood.

E. GWALTNEY.- 

